The ability to forgo a small immediate pleasure or reward in order to gain a more substantial one later.
Although most people show an improved ability to delay gratification as they get older, this important trait appears to be rooted in early temperament. Significantly, people who are most successful in delaying gratification are those with an internal locus of control (a strong belief that their actions can influence events). By contrast, people with an external locus of control are less likely to forego present pleasures for greater future gain.
Mischel, Walter. Introduction to Personality. New York: Holt, Rinehart and Winston, 1971.
Mischel, Walter. The Marshmallow Test: Mastering Self-Control. New York: Little, Brown and Company, 2014.
Nadler, Arie. Delay of Gratification: Review and Suggestions for Future Research. Washington, DC: American Psychological Association, 1976.